1. Technical Field
The present invention relates in general to a communications network, and in particular to voice and data transmission on an integrated communications network. Still more particularly, the present invention relates to a method and system for providing dynamic quality of service for voice and data transmission on an integrated CDMA/1XRTT communications network.
2. Description of the Related Art
Spectral resources (i.e., radio frequency) in telecommunications networks, particularly in wireless networks, are becoming more and more scarce as the volume of traffic increases. The traditional communication systems provided separate networks (or channels) for voice traffic and data traffic because of the various differences between voice and data transmission systems. Thus, most spectral resources were allocated solely to voice traffic and the remaining (smaller percentage of) resources were allocated for data traffic.
Spectral resources are scarce in a wireless network and have to be shared between voice and data services. With the high increase of both voice and data traffic and improvements in technology, the use of separate networks for voice and data transmission has given way to utilization of a single telecommunication network to transmit large amounts of data in addition to the voice transmission. Current implementation of code-division multiple access (CDMA) cellular communications network, for example, provide wireless communication service over a defined service area and allows numerous signals to occupy a single transmission channel in an attempt to optimize the utilization of available bandwidth.
These available transmission resources are represented by a set amount of radio frequency (RF) resources/channels assigned to the particular network and capable of transmitting both data and voice traffic simultaneously. The quality of transmission for both voice and data and the grade of service for data transmission is a growing concern in the industry as both transmission types battle for increase allocation of available bandwidth.
Network operators have started to rollout 1XRTT data service over their existing CDMA networks. This rollout requires the allocation of resources between voice and data services. There are limitations on the forward link power transmitted due to power amplifier limitation and number of Walsh codes available. Therefore, compromise has to be made between allocation of resources for voice and data.
Thus, in many of today's integrated communication systems, both voice and data traffic are carried over shared access networks, i.e., voice and data traffic share the same spectral resources on the air interface. In current RF planning of the resources in a wireless communication system, resources for both services (i.e., voice and data) have to be allocated. However, the service requirements for voice and data networks are different. For example, a voice network requires dedicated channels for the entire duration of a voice call because voice traffic cannot be delayed. On the other hand, data traffic for non-real time applications can be delayed based on established Quality of Service (QoS) requirement. With current designs, the spectral resources are hard divided in two sets (i.e., fixed partitions), one portion (or percentage) dedicated solely to voice traffic and the other remaining portion dedicated solely to data traffic. This hard-division of spectral resources results in below optimal use of scarce spectral resources, drastic decreases in overall capacity of the network due to non-linear decrease in capacity, and degradation of Grade of Service (GoS) and/or Quality of Service (QoS) of the shared voice and data networks.
FIGS. 1A and 1B illustrates fixed-partition implementations of shared RF resources. The entire grid represents 100 percent of the available spectral resources that may be allocated. The fixed amount of power (i.e., spectral resources) allocated to data is plotted on the Y axis as a horizontal maximum data percentage allocation (X %) line 103, which is a percentage of full maximum (i.e. 100%) power line 101. Conversely, the fixed amount of power allocated to voice is plotted on X axis as a vertical maximum voice percentage allocation (Y %) line 105, which is also a percentage of the maximum available power. Notably, voice power allocation (i.e., Y %) is illustrated as a much larger percentage of the maximum available power. Ideally the total allocated power (i.e. X %+Y %) sums to 100% of available power although this is not necessarily the case.
FIG. 1B graphs the actual voice power usage 115 plotted within the power sector allocated to voice transmission from time T1. Voice-Data power separation line 113 clearly indicate the non-changing percentage of power guaranteed for data 123 and that guaranteed for voice 121. As can be seen by actual voice power usage 115, not all of the power allocated to voice is utilized. However, the unutilized power is available only for additional voice transmission.
With the fixed division of the spectral resources, the spectral resources are separately allocated for voice and data transmission. Voice and data traffic cannot overflow into (or utilize) each other's allocated resources even if, for example, data transmission requires more spectral resources at time T1 than X % allocation. This results in inefficient use (or non-use) of the scarce resources. Since there are nonlinear increases in GoS with additional resources (or nonlinear decreases in GoS with decreased resources), the GoS of voice networks is adversely affected by these fixed divisions. Similarly, for the data networks, QoS is adversely affected.
One current approach that addresses the fixed division of the spectral resources allows the Y % allocation for the voice transmission to be expandable into the “fixed” percent (X %) allocated to data traffic. Typically, this permits the voice traffic to encroach into the data RF resources in a somewhat dynamic manner, while still restricting the RF resource allocation for data traffic to X %. With this approach, although the QoS of voice traffic may be maintained, the QoS of data traffic is adversely affected. Also, the spectral resources are used at sub-optimum levels. Additionally, there is no consideration given to cost factors when allocating additional voice bandwidth. Dynamically allocating the data resources to voice without consideration of these cost factors could result in severe financial loss to the provider of these transmission services to paying customers.
FIGS. 2A and 2B illustrate pseudo-dynamic allocation of data power and voice power as a percentage of total spectral power. Vertical window area 204 includes area X % to (100-Y) % of additional spectral power in which additional data traffic may be allocated up to a fixed maximum percentage 203. Likewise, horizontal window area 206 includes area Y % to (100-X) % of additional spectral power in which additional voice traffic may be allocated up to another fixed maximum percentage 205.
With this flexible allocation process, as shown in FIG. 2B, a hard line maximum 219 still exists for data power allocation although the utilized percentage for data may be increased from initial soft line 213 guaranteed for data up to hard line maximum 219. Notably, although data allocation may be extended through dynamic sector 217 of available power, there still exists a significant amount of unused voice spectral resources compare to actual voice power usage 215. This additional unused resource exists regardless of whether or not data transmission is in need of additional resources. With current data transmission of large files, such as image files, requiring significant amounts of available resources, this flexible/pseudo-dynamic allocation still leads to inefficiency and waste of available resources when the actual voice power usage 215 is substantially below the hard line maximum 219. Again, no cost factors are considered during this pseudo dynamic allocation, which could result in significant negative financial implications for the provider of the services. Thus, these current implementations make resource deployment optimization difficult to achieve.
In light of the foregoing, the present invention recognizes that it would be desirable to provide a method and system for improving QoS and GoS for data and voice traffic in a communications network. A method and system, which implement dynamically adjustable spectral resource allocation between voice and data depending on actual need would be a welcomed improvement. It would be further desirable if the dynamically adjustable spectral resource allocations took into consideration cost factors during the determinations of how to allocate the available resources. These and other benefits are provided in the present invention.